SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f00cc0ac11c10dc062d0925c324b3838ff2812540f8a201a2749919104ab59b5' 
  AND token = '5Z6pNZSfYiwndcyOM/b+uNO67am9xJlo9IwPa3z+JO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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