SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2420d27d100a610f3700db892b3992f6abcdaa0ad4620c4d8819d19007a1bd4' 
  AND token = 'W5H7NQowMSBZe01ZcaUBUo7FFHkIcCzG8BgDdJOnUuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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