SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d32c9aac25c3a87b048e039ea751a3fbcdb4dd99eaed6393a930bdf355128d5' 
  AND token = 'RGpfsEuxCaFaDTliN2ZtBDkbpiIJRh80ysH3HEzEQYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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