SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45766240eb366671810ec5ff00cdd0cdf706bd217cee964a0187529de8b7e7f8' 
  AND token = 'zHtJUhaKRRQ9kmBKNRyfY0pu1LFHQs+MLySkEcsHa9k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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