SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eba54d7e5e727635562a3d16ad487bb15fabbc25ee2103e14d457920a29f3968' 
  AND token = '7R30w6BcjqMT8MhpNO+1JG6IM/Ad1GNSwjCNKWnZiYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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