SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a213a374de8bb6fb6afeba950ec17776c8f5d0666da2927450ccc4be16d9d17' 
  AND token = 'fDbQgfEgilPn2wSdmrW8wT+Bj2KCMScqrITrGg2jFCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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