SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54becc6b74f816612957460fa34401774526d66002e2783bb5c48a5a3770dec6' 
  AND token = 'Y/CNXRmQGI9dErUGPlfIQIh+YW2M32paAyiz2PLbALQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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