SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff263bf0a2e428e0b13ae0b966d3c069956045e70f0edbab45f0a4b746d98054' 
  AND token = 'IFqJvjoVD98kG0Mqymyy1xDpgZ7xOIDMqmPePa8qZgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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