SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3817bdd7b4cc9db775457b35f48d5fc4e3b2a590bd01857b02a87d989661f28' 
  AND token = 'onVyfFghvhWEF1r/vhoxnKDA8DtQxETFoCuEO5ms1RA=' 
  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"
    }
  }
}