SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93171ab1e98d858d6f28a1b7bd89d0e469933633bf408951567e3536623975c3' 
  AND token = '8GISAhh3uk/r2mz6gvV9GngVrCQ6NFes+1K5IpmCUPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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