SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e968ea5309e51a9606268fd7f80ec4e10e559ccd1e5cb36108d9d12a73c81190' 
  AND token = '6pyy/zARcXJkbfSFDBjq+j3zxyug1iQFJAVXSLLElTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}