SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad91a4994a711ae38f866a32b5849fd0d3ca31d081b570b26b91069436c8bc22' 
  AND token = '4w7W9Rm+4XCeimmOUbBUeuL8Q2F81/tBY5tOGSp/Kqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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