SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1af4068fd1fc47fa1041af91deb4fdd3bb85ab4a66f28e9dfd9ea9c60a28c47e' 
  AND token = '/0eTNoAGVid4l2RShr+v/P6vgg9mPECNT0YTu8WHAZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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