SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52bcc06077b8b583eb86c26fa72dd6c74d676025cacaebfdc32a1a46e4946498' 
  AND token = 'EaE34PAyBaCm0l4AYfYXQlPCaSGVfd2TWw1cqF5UtyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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