SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd67cf0815ccb28a21060cc413f1fd4a55892b35fbb8e67d3f06a8c7551237d0' 
  AND token = 'HZ+vzIC06hpqvQ2ftcSZRqlWKSaZnqGuWlfKHRkP/tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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