SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffd9ded25c49347d6d21c6d66daf3b383aacf30b2a6f241751bebf41eb820ba1' 
  AND token = 'GCue94caAbTfdVzOkUGds8ffBRvy/BAUBr5Nd1WGhzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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