SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aff6d56ca664f517b6ce52930bff53978848fc5cc06fb376348a1d2b925e3d84' 
  AND token = 'xJxvNCqE+LucwGXxv4ZS/NyAGSysosluGPv2s+h/EMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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