SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9c8132fb7e7c7386b1dabbd4b71cd00bd2d877e0243544916bcc5302bfb806b' 
  AND token = 'kInzO1jyMieebY+P1IIGNEpl8s8xVKgeQ2La1BQeMMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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