SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2583438ad946f328f774337bb714d45e49c12eeb32a99f57b28194460e4bb0d' 
  AND token = 'TBS+oHEtkGxP1HTkcKbQvwdzpKsl0LC5fyhFeTPqNV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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