SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28fe92cbc1d8871ff4d565e9ee12ce60b846b751ab8c6329112b13eda166ab6c' 
  AND token = 'CaCMlH8Dz/oB+Y4NKj+2xrCY1Zyx3ZRjuuxaYcU5fKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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