SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3482296b720e17e4fff765da8206c2fbe599e95023b80edf3d6a17b41744fc80' 
  AND token = 'nLVdlBYgm3MZx0MkVuaTcoIqw6Ax+hs859wdHu8BCbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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