SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb398ce150ed8a18b1603873c527d96489116be8f8be46fbffe8b6709a5923ff' 
  AND token = 'YEsT3qty2OFQgIcsTUGSAv/LR/hYmnM6UWPy7goPQ+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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