SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'aedd7385280cb6410a3ef4dc8eaf6407df2296680e06925d85a46676a0389143' 
  AND token = 'qwsp3UQJgQOrlOMtK+1YcN/zN5PsdWaFWjVMa3ahNQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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