SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '963f45c67734a6a22c0ff5f28b23177dc778b68c5e28bb19e653c5bafdba7245' 
  AND token = 'EKXFS5BUCa5BhmuzSXp3Lv5PdC5jV/1WAQKMH4FHn4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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