SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4ed1a44b7266873a1f94bb8d8fd60262269492b79aa5feb5d9678259e67213b' 
  AND token = 'CZXPi+28KoBIDmaYQKyoIPqLQX8CfkJ/FhXEpSVK6Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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