SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '40db22aaa25e71546128d1d2c60ebd2040825d2d836a20497e2f063fd257181c' 
  AND token = 'ZpnspC81ougVrqCqXaLz9PLfUiAyzPRFXGpbiGw9F9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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