SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74112de5f39ba98b18c57c7d2fbafb22a465095221e013082d36d99c7990b56c' 
  AND token = 'O+Ke9cHE7E+PIXjDrfhQ/xQRorEaJspw86IUWcW60qY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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