SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2114913fb3bc4c109db7fdd621ffc6bca77b6e5c8164d8d441a392fb43b8e2b7' 
  AND token = 'sk7BQW3/qIAzUBgJu2OqWPme+BM+UAOwtxqlwqzOVYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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