SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1dfe2eb86deda1fa2dd74bdf7afb86ceb72e2222d1d86c37a6ef020cc3430db4' 
  AND token = 'fnWoOtpXi+rpQhKsWb4hMNOHpRBTXHozGvoCGLJvsuo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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