SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e661b4a1dbcbf63b0e8c096dc468b147c38264980a883415fc364bdb295a7129' 
  AND token = 'WfGTRH5CG4AE1L2JiPGQX5zL95R6sS+Z5MDKXCtDSqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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