SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8c98f5d0309a55400619b6a179dadd130d375b316b7153f2d1adba91aa6743f' 
  AND token = 'zwspMKAhEzq/Vzz89JB5m4wXk4C0mkfSZrjJAVJgJf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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