SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43578d5bc4946596572fc10b79d6cd6487f71e4a1331b4e04fa4910bbc2f7565' 
  AND token = 'd5QJdRnbQ0Bqpr4+qjdL6htCN8YKTb8FXIvCCu/566g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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