SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f072e6bd2bfbcf95e35761f37c41175f00dc63bd7ac20a1358155342fd538398' 
  AND token = 'XgtGviFC9aZhTKms4B5o7AvjkTwqSdZPJrEL9kOcvXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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