SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd30a1f223571473b1c354b32c4df254d882b6b82942edd0bda1711a75add666c' 
  AND token = 'FkNIvJTR/HgRQlXHfm0zazcjmOCSbDAGZC287eaCRBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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