SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12e00ac000b52cb9057966024ef8595f233e2dd729d67c0a617b212053a2b9c1' 
  AND token = 'mQFkOiFDvyvLEO5I/xMKw8PZuk1VEQfIAa5wOF4ipOg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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