SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92e2ae993eb7351c4442d3441c517a8865f88ceaff6c30699abc06e380bd009b' 
  AND token = 'RsWO2+FU7JQRlJvzlrQYBPUX7zILDTgja0IClVemILI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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