SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a5fe6ff3010958ded142c6fb538ea3964c5f0cb205f39817d36980f508e18f6' 
  AND token = 'rmYbl0xhtoiI9cCsFkWE7yriYWJL27dkofUQqXOXBhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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