SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30ff526bc5ff6d1609bb1a9ca91cf8772fedcf80ce603821a64208337aeeb4ef' 
  AND token = '79Scxw245HdI4MaLwFt3conjCHMekFmFN/XgwZqyIsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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