SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94bbff84dd6d13d2d6a0aa651ede411e67960cc2487ca9e67b0a627236228e3f' 
  AND token = 'acdtXGtgF14vWvOsUjtG4J/f6vK5Ht8lAGqD9khpLok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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