SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fba903583e8906d0210f7f998fd0a6c7be6b93439a4c4a788fac259692727538' 
  AND token = 'cYrdW98pnswSNuTUfsX68jBSeJ0RY7Dz5iKLgF99MWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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