SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2144616849ad34e4dd93be2c54922084260d5503474706c127b844e755883548' 
  AND token = 'eGaKNyfEuYqSmXTZ2BD69q+jxZSNpnz9Xa0+QSoIwu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}