SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54147e1d970daf95ce68009f7eb7e8ebbb132344831cf67677babb51436a166b' 
  AND token = '+rgTKdti8nHJtuj0Yg+D5H9MN3K2aHImJgA6/wsV+vY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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