SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c20fd0a3a8e6491c8637d46a03d2523ec89fe07abdf2e5573742c832ab28877f' 
  AND token = 'nyH6qEXsUGVNgPMVMhVs7IFRCumJ8CNW2ckl+wFA4q8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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