SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9b38f91bfcc86ab7ddfa4849cea84bf4e2aa070ff87443ac25b2c656deaf433' 
  AND token = 'dAh6VII1AfN54YWd1hzo/acQXTXC9io0GXrKiGjUJmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}