SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbae2fc8d82cdc789698f1c852ffa4a86f1bcc3eaa3b516c37fa41cf6cf45977' 
  AND token = 'QB6dBBFipxfF7xKUjuuozY2XhQAUZ2Xiu2s+0nEwcx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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