SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05cf2102bb9237d911cb8668e69ff1bbd50a09b267b365471fd7aa8c417759f4' 
  AND token = 'ZcAZLN8UHhg6n4B8IGd/Fk5+vaCUFVPx64yhR+7qXzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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