SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e080a0150597a08485206c8357ebd6a92879897755a5f4c887c3f7afc84346c2' 
  AND token = 'L9L4/x9XwqNF0S/+453AbcVUd5IkBqEvM7cJ7pLKKsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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