SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bcaf6ffd738ac4f9f64dcaf698d021a4233c2aacee748d47a734cb304dbe1937' 
  AND token = 'F6IaFFrqXST2nnCucSvfQj66U+IYf4jmTwBuZKcvdFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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