SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '199f3da7a4c1d9916a830ab9fc94da1927a4fd2b1fe8c2eeb38598678c6f1e27' 
  AND token = 'hI0YhQr9Xq6fjLxeWTPllFDeVSVevbtMwSYEiFEZEno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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