SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '099d8a9fd1a8e800e9b601cdb9fa002f6a6d625c30a90d9ac245d570b5557e3d' 
  AND token = 'Ad6B+LOJPw9g/62JUf9on5YBD6yJ3SYQHNRe0bVt1E4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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