SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7024087a7deab88629e4ea84d314a5054525f1aea626c7893f2dd161ffc47f5' 
  AND token = '0hgvgLBOJtj07+NuIhFVvTJm+ZDh6wwtdacBjzxlFoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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