SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7eeac83f253231908a136072d325058d8ae207690a5ac3f5672aa098f0e671b9' 
  AND token = 'YHcfoq3rhNcolofQ9qDjjMeAQdb8Jit9tnv8EJcPQU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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