SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74c7439e7ff4a5ba742c0e54ff6644d53de796602a402487fcd8a9ae0186f7f1' 
  AND token = 'OGzNyRd5BQkh97pVMzATzkY+speyhDgf24ARbP8VAos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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