SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '050cf426d85291d3de1dcf617f9c7a347948ae7cd27ec66405ddb31ec9cf2327' 
  AND token = 'PIp9UlrDzzn8aQICVfHbpApANRo3bGIvh2Fc9VgfSlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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