SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6960f5d655bd66b57124ed8f193dbce4ff7eb19315f99cf82b40668d29cdcb77' 
  AND token = 'UsFpKgdG7S4Py1BRe0uIagDx2PQ7UaTN2uINLwkfYbI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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