SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '46d9c7b34a6f62a69188a6f190700a238a601c5d80130d0eb2ff19b4c2b26190' 
  AND token = 'vvT3kqadCsqvtzwNiWKVgZmm9KbqGU3VPKiCBHBkQdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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