SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '211868d4baf8dd7569396a5b761d0a4e3fa8f2b3f6207e317d686c14294692e1' 
  AND token = 'GWpGEXNMSrmK7+Fst0viBpSgson3NyWu7K5ZVDaC2Ag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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