SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '35f66d32a01bdd19890fa3c8344436fcfad191b427d421a91871c5ffc19f49c3' 
  AND token = 'Jjq1kzcmmqCKdBzO1mpfHmP+77GtDtIvAhzr7AraMwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}