SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd441606e5b2dec1303d55805a035293a7ad72c0ad3c445361018a3fb3945fad7' 
  AND token = 'Bm6fcJDalmRzGDYfN8LhSaz1GuRI9kLaku/TFD9U0iE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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