SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5145277d8d9ec078b186e89c3e5c1ca48a595bdeeaaffbe0533241cbd7d4d764' 
  AND token = 'gC/4YwVvnBSNfntsMpCwZjbw19A7jLkKNSbelCuKF+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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