SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a0d9b8fec122d5e06b1541649a7bc18f2cc1097db89988b55f6a228c4def1d2a' 
  AND token = 'HZQIEl2oIklPXNTuf2Xt5Xc2C6pOa0QTWfsG1S4f29Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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