SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '604aba5814ec3374094a6ed7963f5b493d94f0fa629f63b1e1d592dd70282c19' 
  AND token = 'KQIAREzuXl1UQ1z1PJsx24ecrbQjAAsD/A9+Sm3xsQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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