SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '053b7e4cdbca60e443fb9e6fe00a0392c634ff2222edb5afdb45dffda840be5e' 
  AND token = 'ebHDH0L4MMLEIzLqsEjiBQfJkh3XoDEagthuEYfEMTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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