SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd8e3c052be17de280b5545e904ec021772e5b8ae0c8691e37bc02fe726ad627' 
  AND token = 'AS/8g+/C4hhOtju5snWGekeCIWlZTv7WWfyqCVFDTLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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