SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dc86fa653ddbb9330af1fcfec4e560d275243318ae74578f85cbff060cdabad' 
  AND token = 'Azllt7nZBpgqlHWv4vt4VFXBcWgkmvhIwEfxduRLruU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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