Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bc42c8defb3dd5c82d7738c2da90f46084e4582bf6189fbcfe44c59bd2c5c1d8' 
  AND token = 'ldKFaMoV4wK4sQ3N5xdkoG/K6KA36JepHUOlDae8Dqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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