SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '76da69ccccfa230f7b388e8215ce29720fead3ba4be999d4bce9cf3802f7aa72' 
  AND token = 'Htg1Z5sVP9CobLXjjlvzQXxvgO0E/0q9hR1jhxj5frU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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