SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2731b73f27fbd7deeb4852e7d6214e386758fe21de712dc369e88a123884f59d' 
  AND token = 'w/lyYY19hVLVTXlPK/tkF8LL5SqEjfE54IopXeCpqjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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