SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8962d9c3e29ef2ead832efc52c89e28daa923cdf8f2c905e623e4276ada5ae13' 
  AND token = 'gV2VVH6NqeVRUVJ/CGUVHImc4S7zAuMwlXBN7BWSExo=' 
  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"
    }
  }
}